1. Field of the Invention
The present invention relates generally to sensors for machines with moveable components and more particularly to a device and method for sensing the absence or presence of sheet products.
2. Background Information
Many machines contain moveable components that circulate around the machine continuously. For example, a collating machine is comprised of a plurality of carriages that continuously circulate around an endless loop. Each carriage contains a plurality of pockets. A product from a stationary pile is deposited into each pocket as the carriages circulate.
Collating machines may be useful for properly collating printed products in a specific order. Inserting machines are collating machines in which printed products, such as newspaper sections, are placed within each other. For example, the sheets or sections in a book or newspaper must be in the proper sequence before binding or assembling. The plurality of pockets are arranged at regular distances apart and are moveable along an endless path. Each pocket receives a first product. The pocket then moves downstream and receives a second product. For a collating machine to function properly, the first product must be properly deposited into the pocket before the deposition of the second product. An improperly deposited first product or the failure of depositing the first product will cause downstream errors. These errors include misarranged or missing pages in a book or newspaper or partially deposited products that may cause malfunctions of the collating machine by obstructing movement of the pockets along the endless path.
U.S. Pat. No. 5,251,888, for example, purports to disclose an insetting machine with pockets. No sensors appear to be provided.
Japanese Patent Document Nos. 99-059975, 99-079429 and 98-338360 purport to disclose paper sensing devices but do not appear to address the problem of sensing paper as the paper is located in, or directly enters, moving pockets.
An object of the present invention is to provide a method and device for inserting and sensing a product in a pocket of a collating machine. Another alternate or additional object of the present invention is to provide a method and device for sensing a product on a moving machine while the sensor and the associated electrical power and signal wiring is stationary. A further alternate or additional object of the present invention is to provide a method and device for verifying the proper operation of a moving machine. Yet, a further alternate or additional object of the present invention is to provide a method and device for detecting an obstruction in a moving machine. A further alternate or additional object of the present invention is to allow the use of photodetectors to detect products or machine elements on moving equipment. Yet, a further alternate or additional object of the present invention is to provide a method of using fiber optics and photodetectors to transmit information from a moving platform to a stationary control station.
The present invention provides an optical sensor for detecting the presence or absence of sheet products in a moveable device, the sensor including a fixed light source, a fixed light detector spaced from the fixed light source, and a light transfer device fixedly connected to the moveable device for directing light from the fixed light source to the light detector as the moveable device passes by the fixed light source.
The present invention advantageously permits for reliable and effective device for sensing of products entering a moveable device or for detecting paper jams in the moveable device.
The light transfer device preferably includes a first optical fiber having a first lens attached to a first fiber first end and a second lens attached to a first fiber second end. A second optical fiber may have a third lens attached to a second fiber first end and a fourth lens attached to a second fiber second end.
The first optical fiber and the second optical fiber may be fixed to a top of the moveable device. Preferably, the moveable device is a pocket of an insetting machine. The first lens may be spaced by a distance from the second lens. The first lens and the second lens may be located so as to align with the fixed light source and the fixed light detector as the moveable device passes the fixed light detector and the fixed light source.
The moveable device may have a first opening on a first side and a second opening on a second side of the moveable device. The third lens may be located so as to align through the openings on the first side and on the second side with the fourth lens.
The fixed light detector and the fixed light source are preferably located opposite a conveyor rail conveying the moveable device. The fixed light detector and/or the fixed light source may be connected to a stationary control unit.
The present invention also provides a device for placing products into a moveable device including a plurality of moveable devices and a plurality of optical sensors for detecting the absence or presence of products in the moveable device or for verifying the functioning of the optical sensors.
The present invention advantageously permits for a reliable and effective device for collating, including inserting, products in a moveable device.
The optical sensors include a fixed light detector spaced from a fixed light source by a distance, and a first and a second optical fiber fixedly attached to the moveable device. The first optical fiber may have a first lens attached to a first fiber first end and a second lens attached to a first fiber second end. The second optical fiber may have a third lens attached to a second fiber first end and a fourth lens attached to a second fiber second end.
The moveable device may have a first opening on a first side and a second opening on a second side of the moveable device. The third lens may be located so as to align through the openings on the first side and on the second side with the fourth lens.
The fixed light detector and the fixed light source are preferably located opposite a conveyor rail conveying the moveable device. The fixed light detector and/or the fixed light source may be connected to a stationary control unit.
The invention also provides a method for detecting the absence or presence of products in a moveable device by an optical sensor or for verifying the functioning of the optical sensor including inserting the product into the moveable device of a machine. The moveable device is then aligned with a fixed light source and a fixed light detector. Then, the fixed light is transmitted from the fixed light source. A first optical receiver located on the moveable device then receives the light through a first lens attached to a first fiber first end of the first optical receiver. Then, the light is transmitted through a second lens attached to a first fiber second end of the first optical receiver and across a first opening on the first side of the moveable device. The receipt of the light across a second opening on a second side of the moveable device and through a third lens attached to a second fiber first end of a second optical receiver located on the moveable device is then determined. Then, the receipt of the light through a fourth lens attached to a second fiber second end of the second optical receiver at a fixed light detector is determined. A signal from the optical sensor is then transmitted to a stationary control unit. Then, the signal is processed by the stationary control unit. A plurality of secondary signals is then sent to other controlling modules for the machine.
The present invention advantageously permits a reliable and effective method for sensing products in a moveable device by an optical sensor or for verifying the functioning of the optical sensor. The present invention also advantageously permits a reliable and effective method for verifying the functioning of an optical sensor.
The optical sensor may further detect the absence or presence of products in a second moveable device or may further verify the functioning of a second optical sensor. The moveable device may further align with a second optical sensor to detect the absence or presence of products in the moveable device or to verify the functioning of the second optical sensor.
Preferably, the first optical receiver and second optical receiver are optical fibers.
xe2x80x9cSheet productxe2x80x9d as defined herein may include sheets and/or signatures.